(Forgive me if this should be somewhere else - I can't work out where bugs should be reported.)
On a fresh install of Bodhi (3.2.1, 64 bit), double-clicking an executable file gives you the option to Execute or Execute in Terminal.
Execute in Terminal tries to run the program from x-terminal-emulator, which isn't installed by default. The terminal can be changed to terminology in the file manager's perferences, but this shouldn't be necessary - it should be set up correctly from the beginning.
(PS. Do you really need 3 different captcha things to sign up for an account?)